Pipe bending equipment



March 13, 1945,. J. R. HORRIGAN 2,371,393

PIPE BENDING EQUIPMENT Filed Jan. 28, 1944 2 Sheets-Sheet 1 mm iMarch13, 1945.l .1. R. HORRIGAN PIPE BENDINGEQUIPMENT Filed Jan. 28,1944 2 Sheets-Sheet 2 Patented Mar. 13, 1945 UNITED STATES' PATENTOFFICE PIPE BENDING EQULPMEN T v Joseph R. HorrigamlHouston, Tex.Application January 28, 1944, Serial No. 520,114 2 claims.' grasse-32)This invention relates to -pipe bending equipment.

An ob-ject of the invention is` to provide equipment of the characterdescribed designed to be used in the process of bending pipe so that thepipe will not become distorted at the bend but maintain itsapproximately round contour. v Another object of the present inventionis to provide equipment for transversely corrugating the pipe on theinside of the bend, or curvature, to the end that the pipe will` notbecome distorted, at the bend, when it is bent.k

More specically it isran object of the present y invention to provideequipment '01 the character described whereby pressure may be exerted,outwardly, against a limited area'of4 the inside of the pipe and at, oralongQthe inside vof the bend so that an outwardly extended transverse corrugation, or corrugations, may` be formed in the pipe at the insideVofthe bend which will facilitate the bending operation and prevent anysubstantial distortion of the'pipe.'

At the present time, pipe is lbeing manufactured having much thinnerwalls than heretofore and it has kbeen found that when it is attemptedto bend or curve pipe having these thin walls that the pipe will becomedistorted and in some cases collapsed at the bend so as to refstrict thecapacity of the pipe and the volume of fluid capable of flowingtherethrough. This type of pipe is commonly used in the construc. tionof pipe lines for conducting gas, oil or other liquids and it isessential that its full capacity be maintained.

The present invention has been ,designed so thatthe pipe can be bentwithout distortion and Without reducing its capacity.

The invention also comprehends a novel process of bending pipe.

invention has particular relation to certain novel features ofconstruction, operation and arran`gement of parts and to a novel methodan example of which is given in this speciicationand illusf trated inthe accompanying drawings wherein:` Figure 1 shows a side elevation,partly in section, of the equipment as applied to the pipe.

Figure 2 shows a sectional view of the pipe and its. clamp before thepunch and its operating f mechanism have been inserted, and rotatedclockwise through an angle of 90 degrees, taken on the line 2-2 ofFigure 1.

Figure 3 sho`ws a transverse sectional View, rotated clockwise throughan angle of 9U degrees,

of the pipe and matrix after the pipe has been fully bent against thematrix. .f

Figure 4 shows a side elevation of the punch.

1 Figure 5 showsv a transverse sectional view of the Apipe showing thepunch an-d punch oper'- ating 'mechanism therein partly in section'and,

'Figure 6 shows a longitudinal sectional view takenon the-` line S-ofFigure 5.

- Referring now more particularly to the draw-y ings wherein likenumerals of referencev desig-` nate the sameparts in each of the guresthe numeral I designates a matrix Whose outer side is curved from end toend, having the curvature which it is desired to impart, to the pipe 2to be bent. l'I'his matrix is also curved transversely, as shown inFigure 3 to snugly receive said pipe. The matrix may be secured to, orformed integrally with, a plate 3 which,4 in turn, may be .bolted orotherwise secured to a truck or ablefavailable anchorage.

'As -illustrated the matrix is so mounted that the pipe will be swungina horizontal plane during the bending operation. y i'Ihe matrix isprovided with a transverse opening 4 through the bottom thereof land ifit'be desired to form more than one corrugation in the bend of the pipethe matrixy may be provided withadditional openings as 5 and 6.

It is. apparent that the matrix may be provided with mere indentationsrather-than openings. l

The numeral 'I designates a punch designed to any other suitcooperatewith the matrix to form a 'corruga- Y t With the above-and otherobjectsin view'the tiony'or cOrrugatiOnS, as 8 inthe pipeon fthe insideof the bend.

This punch 'l hasthe external arcuate rib 9 thereon which is broughtinto registration with a corresponding opening in the matrix and whenthe pressure is applied forces the contacting portion'of the 'pipe intosaid opening to form the corrugation.- l y f "The punch member l, of thedie, may be made ofv any selected width and is of ageneral arcuate form..Opposite the punch member and of approximately the 'same generalcontour, there is a basememberv l0 which forms a support for a jack Il.l `Any type of jack or otherV expanding and contracting equipment maybe employed either hydraulically, mechanically or manually operated'. Inthe present illustration a gear jack is shown. This jack may be securedto the base member I0 and includes the threaded shaft l2 which operatesagainst the punch memberl 1.

The members 1 and l0 may b'e mounted on a carriage consisting of thefront and rear axles of suitable depths I3, I4, which carry therespective rollers I5, I6, and the axles are mounted in the front andrear arms I'I, II and I8, I8 carried by the respective members 1 and I0as shown in Figures 1, 5 and 6. The equipment may accordingly be `movedinto the pipe traveling on the rollers I5, I6.

The jack illustrated is the conventional type of gear jack and may -beinserted into the pipe and operated by the shaft I9'whose outer end maybe provided with the hand wheel 20.. This shaft is supported by, androtates in the bearings of, the supporting spiders 2|, 22 the latter ofwhich may have the antifriction rollers 23, 23 to roll against theinside of the pipe.

The section of pipe to be bent may be vlai-d in the matrix I as shown inFigure 1 and oneI end.

of the pipe may be clamped in position by any suitable means and thebending forcer may be applied to the other end of the pipe by a blockand tackle arrangement or by any other means providedso as to cause thepipe to conform to the longitudinal curvature of the matrix at the pointwhere the pipe is to be bent` The clamp means above referred to mayinclude the lower anchor 24 which may be welded, or otherwise secured,to the plate 3 and may also include the arcuate clamp jaw 25 which ishinged at one end to the anchor 24 and whose other end may be latchedaround the pipe by the latch mechanism 26 which in turn is hinged topivot on a vertical axis so that it can be swung horizontally out of theway when it is desired to locate the pipe in the clamp. When the end fthe pipe section is secured in the clamp and the pipe section isiittedin the matrix and the bending force is ready to be applied thecorrugating equipment may be inserted into the clamped end of the pipesection and moved in- Wardly until the rib 9 is exactly opposite theopening of the matrix into which the corrugation is to be forced. It isshown opposite the opening 4 in Figure l. The shaft I9 may then beturned in an appropriate direction to force the punch member 1 outwardlyand the rib 9 vwill force the opposing section of the pipe into saidopening forming the transverse rib or corrugation 8 and the bendingforce should, preferably, be applied just after the formationof thecrimp, or corrugation, is started. At the same time the arcuate basemember I will be forced against the opposite side of the pipe and willhold it to its original round contour.

The pipe ts snugly in the `matrix member I and will be prevented, by it,from becoming out 0f round.

If it be desired to form morethan one corrugationthe rotation of theshaft I9 may be reversed to'release the jack and to withdraw the rib 9from the corrugation just formed and the equipment may be moved furtherinto tlie pipe until the rib 8 is opposite the opening 5 and anothercorrugation formed, asbefore, andv so on until thedesired number ofcorrugations have been formed, it being understood that the pipe willgradually be bent to the curved shape of the matrix as the inside of thebend is corrugated.

When the work has been completed, the jack II may be released so thatthe equipment inside l. Pipe bending equipment comprising a frame,

a matrix fixed rigidly on the frame and whose operative face is curvedtransversely from end to end to receive and embrace one side of the pipeto be bent, said face being convex longitudinally to conform to thecurvature of the desired bend in the pipe, an assembly insertable intothe'pipe to 4a position opposite the matrix, said assembly comprising abase member Whose outer face is curved to conform to the contour of andto fit against the interior of the pipe on the outside of the bend and acomplementa] punch member whose outer face is curved to conform to theshape of and to t against the interior of the pipe on the inside of thebend, said face of said punch member having an external arcuate ribthereon positioned transversely. with respect to the pipe, said matrixhaving a transverse arcuate space of sufficient length and depth tosubstantially receive therein said arcuate rib, and means for expandingsaid base member and said punch member to force said rib and adjacentpipe .area engaged by the rib into said transverse arcuoperative face iscurved transversely from end to end to receive and embrace one side ofthe pipe to be bent, said face being convex longitudinally to conform tothe curvature of the desired bend in the pipe, an assembly insertableinto the pipe to a position opposite the matrix, said assemblycomprising a base member whose outer face is curved to conform to thecontour of and to fit against the interior of the pipe on the outside ofthe bend and a complemental punch member whose outer face is curved toconform to the shape of and to t against the interior of the pipe on theinside of the bend, said face of said punch member having an externalarcuate rib thereon positioned transversely with respect to the pipe,said matrix having a plurality of transverse arcuate spaces ofsufficient length and depth to substantially'receive therein saidarcuate rib,

said assembly being movable to locate the ribA

